To protect devices, such as integrated circuits (IC), against electrostatic discharges (ESD), in some examples, a power clamp may be placed between the supply and the ground line to limit the ESD voltage below a destructive level. A metal oxide semiconductor (MOS) transistor may be used as a shunt path in a power clamp as a MOS transistor may be triggered in a controlled way. ESD currents may be in the range of several amperes, so for an IC the MOS transistor may use a width of many millimeters or a smaller MOS transistor device may be used in the parasitic bipolar mode to shunt the ESD current.